4. How do I search for the evidence?
4.2. Search terms
5.2 Search terms
Once you have written your question (see the Ask section), use the PICO or SPICO terms to help you build your search strategy.
Here is an example using (S)PICO i.e. including species:
In [cats with naturally occurring chronic kidney disease] does [a renal prescription diet compared to normal diet] increase the [survival time] of affected cats?
Make a list of the key concepts needed to build your search.
In this example, the key concepts for the search strategy would be ‘cats’, ‘kidney disease’ and ‘diets’.
Note: The (S)PICO and the Search Strategy are not the same thing!
It is likely you will not search on all your (S)PICO terms. For example, 'Outcome' terms are often excluded from a search because they can be broad terms with many alternatives, meaning key articles may be missed if they are used. Also, outcomes may not be mentioned in the abstract, particularly if the outcome is recovery.
Think of synonyms and alternative terms for each concept. Click the cards below to show examples of these.
English and Latin terms
Alternative spellings for your terms
Examples of UK English/American English spellings and usage
Abbreviations and acronyms
Nonsteroidal anti-inflammatory drug
Anterior Cruciate Ligament
Bull Cow Calf
Chronic Obstructive Pulmonary Disease
Be as specific as possible, and where you are interested in a broad topic, e.g. kidney disease, list the more specific topics, e.g. types of kidney disease, that you want to cover.
Table 7: Examples of specific topics related to kidney disease
Chronic renal failure
Chronic renal disease
Chronic renal insufficiency
Chronic kidney failure
Chronic kidney disease
Chronic kidney insufficiency
Figure 3: Breaking down a topic to maximise search effectiveness
This diagram shows how you might break down a topic (diets in cats with chronic kidney disease) into key concepts (diets, cats, kidney disease) and then use synonyms or related terms for each concept in your search strategy.
For example, under 'diets' you could search for renal diet, kidney diet, prescription diet and therapeutic diet. Under 'kidney disease' you could search for chronic renal failure, chronic renal disease, chronic renal insufficiency, chronic kidney failure, chronic kidney disease and chronic kidney insufficiency. Under 'cats' you could search for cat, feline, felines and felis.
This will maximise retrieval of relevant publications, as authors may use different terms to describe the same concepts.